The Change Of Soil Phosphorus And Potassium And Yield Response Of The Region Of Winter Wheat-summer Maize Rotation In Hebei Province

At present, more and more extensive use of chemical fertilizer and the misuse offertilizer are more and more manifest in our agricultural production. For the current thatfarmland soil nutrient continued accumulated, and the problems of decreasing yield effecton phosphorus, potash. In this paper, based on the topography, soil parent material andhuman activities, the main factors affecting soil development as an entry point,combination the macroscopic soil potassium, phosphorus nutrients changes and thewheat-maize rotation yield of field trials, statistical analysis of the second soil survey data,Gaocheng, Xinle, Xinji, Wuqiang four counties (cities), for example, analysis of the twoterrain soil nutrient changes of Taihang piedmont wheat-maize rotation district aspiedmont plains, plains area in three decades and the characteristics of agriculturalapparent balances of phosphorus and potassium. By investigate of fertilization, soil fertilityand crop yields on wheat-maize rotation area after the second soil survey, use the methodof field trials, pot experiment and simulation of soil to study the transformation ofphosphorus, potassium in soil and effect of straw on soil phosphorus, potassium, provide ascientific basis to quantitative assessment of the effect for phosphorus and potassiumfertilizers on soil nutrient, and put forward a rational fertilization under straw incorporation.Main conclusions are as follows:1. The crop yield of wheat and maize rotation area showed an increasing trend inHebei Province. The winter wheat yield increased by48.20%in year2012compared to1994, and the maize yield increased29.83%compared to1994. A huge increase of cropyield showed in the piedmont plain and plain area. Sown area floating slightly, show anupward trend. Fertilizer inputs increased by year, in2012, the fertilizer consumptionincreased192.16%than1989，reach to516.11kg/hm2, the fertilizer consumption in plainarea increases larger than mountains and piedmont plain area. Straw incorporation area inHebei province is increases by year, in1981straw incorporation area is2.3×104hm2, to2012, the area is growth to3.4×106hm2.2. The winter wheat yield increased by31.45%in year2012compared to1994, andthe maize yield changes. Fertilizer inputs increased by year, in2012, the fertilizerconsumption increased125.11%than1989.The Taihang Mountain, piedmont plains, plainarea show a growing trend of soil phosphorus and potassium. Compared with the secondsoil survey，soil P increased，and K decreased slightly. P balance index was increased, K balance is deficit. Three terrains show differences in nutrient accumulation. Gaocheng,Xinle two counties (cities) of piedmont plains, xinle soil available phosphorus raise to35.09mg/kg form6.15mg/kg in the second soil survey, Gaocheng raise to37.15mg/kgform9.00mg/kg, Gaocheng K raise to113.2mg/kg form109.5mg/kg，Xinle K decrease to89.1mg/kg form106.4mg/kg; Wuqiang in plain area, Phosphorus raise up to24.06mg/kgform5.26mg/kg. K reduced to111.1mg/kg form143.5mg/kg. In the current productionconditions, excessive inputs of phosphorus is the main cause of phosphorus nutrientaccumulation, And the crop yield increases resulting in higher soil potassium depletion,soil potassium slight decrease.3. Phosphate fertilizer application on different levels of soil Olsen-P significantlyincreased soil Olsen-P content, and the unit volume of soil phosphate fertilizer addition inOlsen-P of the soil is increased with the amount of soil Olsen-P, the difference wassignificant. Both use P fertilizer only and straw coordinate with P fertilizer, soil phosphorusfixed rate increases with time growth, straw application significantly reduced the rate ofsoil phosphorus fixation. Potash fertilizer application on different levels of soil available Ksignificantly decrease by soil available K content.4. When the use of phosphate fertilizer is45~135kg/hm2, straw or not, effect on wheatyield respectively an increases of8.4%~26.9%and6.2%~21.2%, the difference wassignificant. Using phosphate fertilizer22.5~67.5kg/hm2, straw or not, effect on maize yieldrespectively an increases of5.6%~46.8%and14.1%~43.1%, the difference was significant.When the use of potash fertilizer is22.5~67.5kg/hm2, straw or not, effect on maize yieldrespectively an increases of5.0%~20.5%and6.1%~19.7%. Using potash fertilizer45~135kg/hm2, straw or not, effects on maize yield respectively an increases of13.2%~46.4%and6.9%~36.2%. Straw significantly increased the effect of phosphate andpotash fertilizer on the yield of winter wheat and summer maize.5. According to the yields and nutrient balance, under straw incorporation,winterwheat field reach7500~9000kg/hm2,the P2O5, K2O fertilizer recommendation is45~60kg/hm2and30~60kg/hm2. Under straw incorporation,summer maize,the P2O5, K2Ofertilizer recommendation is30~45kg/hm2and45~60kg/hm2.